Cystine reductase

In enzymology, a cystine reductase (EC 1.8.1.6) is an enzyme that catalyzes the chemical reaction

cystine reductase
Identifiers
EC no.	1.8.1.6
CAS no.	9029-18-9
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / QuickGO
Search PMC articles PubMed articles NCBI proteins

2 L-cysteine + NAD⁺ ${\displaystyle \rightleftharpoons }$ L-cystine + NADH + H⁺

Thus, the two substrates of this enzyme are L-cysteine and NAD⁺, whereas its 3 products are L-cystine, NADH, and H⁺.

This enzyme belongs to the family of oxidoreductases, specifically those acting on a sulfur group of donors with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is L-cysteine:NAD+ oxidoreductase. Other names in common use include cystine reductase (NADH), NADH-dependent cystine reductase, cystine reductase (NADH2), and NADH2:L-cystine oxidoreductase. This enzyme participates in cysteine metabolism.

References

• ROMANO AH, NICKERSON WJ (1954). "Cystine reductase of pea seeds and yeasts". J. Biol. Chem. 208 (1): 409–16. PMID 13174550.
• Carroll JE, Kosicki GW, Thibert RJ (1970). "Alpha-substituted cystines as possible substrates for cystine reductase and L-amino acid oxidase". Biochim. Biophys. Acta. 198 (3): 601–3. doi:10.1016/0005-2744(70)90137-3. PMID 5436160.
• Maresca B, Jacobson E, Medoff G, Kobayashi G (1978). "Cystine reductase in the dimorphic fungus Histoplasma capsulatum". J. Bacteriol. 135 (3): 987–92. PMC 222474. PMID 211119.